FAQ

There is a web-type coating on the limbs of one of our valley oak trees. It has never happened in the 12 years we have lived here. It looks like a sleeve of webbing, thin and solid, starting at the trunk and going up several limbs. We have four trees spread out, and only one has it. What might it be, and is it bad for the tree? It has been there for about two weeks and is starting to get less.

This is likely an insect called a leafroller that created the webbing. If this is a leafroller causing the webbing, it has probably completed its life cycle. If you see a reoccurrence next year, you can treat with insecticides including organic products such as insecticidal soap.